Tiger Woods won't be defending his title at golf's unofficial fifth major this weekend, and it's unclear which official ones he'll be back for as well.

In a somewhat long-winded blog post, the 14-time major winner explained how he still cannot reach down to recover his ball from the cup while having putting contests with his son and how he has yet to swing a sand wedge or any larger club.

Although he's staying positive in his rehab from microdiscectomy surgery in his back, Woods wasn't able to put a definitive date for his return:

As for my return to golf, I really don't know. I'm doing everything I can and listening to my doctors and working on a strength program, and then we just have to see how my back is. Some people heal up in three months, some people take four months, some people take longer. I just don't know.

Adding onto that, Woods said he has talked a lot to Tony Romo, who underwent the exact same procedure. The Dallas Cowboys quarterback began throwing May 6, a little more than four months after his surgery.

For hypothetical purposes, three months—Woods' low estimate—would take us to early August.

Not only would Woods miss The Players Championship at Sawgrass this week, but that timetable would keep him out of the U.S. Open, the Quicken Loans National (which he hosts) and The Open Championship.

The fourth and final major of the year, the PGA Championship, may be a good bet for a potential return in this particular scenario, as it takes place August 7-10.

Still, though, there's no definitive evidence that three months is his actual target for a return, as he went on to explain he hopes "to be back sometime this summer."

For what it's worth, the oddsmakers, via Yahoo! Sports' Shane Bacon, are still holding out hope he'll return to Pinehurst in June:

Of course, while Woods said his recovery was a slow process, he did offer some encouraging words:

One reassuring thing from my medical exam is I have zero arthritic changes whatsoever. I've kept myself in very good shape over the years, and it has paid off. We knew going into this procedure that it really helps to be strong, especially in my glutes and my abs. I was strong in both departments, and that helps with the recovery and rehab, and you're able to come back faster.

It's anyone's guess at this point; even Woods himself doesn't seem to have a precise plan, noting that he has conference calls with doctors every few weeks and is still doing "tedious" rehab tasks.

Twice has Woods missed two consecutive majors in his career.

In 2008, he missed The Open Championship and PGA Championship after undergoing ACL surgery. He finished sixth at the Masters upon his return but hasn't won a major since.

Jamie Squire/Getty Images

In 2011, he missed the U.S. Open and The Open Championship with knee and Achilles problems. It took him a little longer to get back to form that time around, as he missed the cut at the PGA Championship and plummeted in the world golf rankings.

And while his uncertainty leaves a lot to the imagination, it sure seems likely that Woods is headed for the third such extended absence of his career.

He has proven us wrong many times before, though, and it still wouldn't be surprising if Woods is back chasing Jack Nicklaus' major record sometime this summer.